JP4020499B2 - Friction material wear warning device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a friction material wear warning device that electrically detects a wear limit position of a friction material constituting a braking member such as a friction pad and a brake shoe and warns a driver.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a friction material wear warning device has been proposed that notifies a driver by an alarm sound or a warning light when a friction material reaches a wear limit.
[0003]
This conventional wear warning device (see Japanese Utility Model Laid-Open No. 50-117286), as an example (Example 1), is provided with an opening at the edge of the back plate to which the lining is fixed, and the detection terminal from the side opposite to the lining. The opening is inserted and fixed. However, it has the following problems.
<I> A tool such as a pliers is required to attach and detach the retainer.
<B> Since there is no detent means for the detection terminal, the wire (electric wire) is twisted and damaged, or the tip of a general wire is U-shaped, and there are many types that detect this disconnection, The two wires are not positioned in the direction orthogonal to the member to be braked, and the detection capability is reduced.
<C> The detection terminals and parts for attaching them to the back plate must be managed separately, which is cumbersome and cumbersome to assemble.
[0004]
As another example (example 2), a blind hole that penetrates into the lining through a back plate of a portion to which the lining is fixed is provided, and the tip of the detection terminal is disposed in the blind hole. The head of the detection terminal is covered with a frustum-shaped insulator, and the mounting relationship between the detection terminal and the back plate is that after inserting the head of the detection terminal into the hole, a washer is inserted and a back plate is further attached. It has been partially caulked. However, it has the following problems.
<I> A special machine for caulking is required.
<B> Since there is a risk of damaging the insulator and lining during caulking, the condition management becomes strict, and the arrangement direction of the two wires of the detection terminal must be correctly arranged, which is troublesome. .
<C> There is also the problem of C in Example 1 above.
[0005]
As another example (Example 3), when the detection terminal is fitted into a blind hole provided in the back plate, and the back plate is thick, the detection terminal is inserted into the blind hole, and then the spring washer is press-fitted and removed. If a stopper is applied and the back plate is thin, a cylindrical stopper is press-fitted. However, it has the following problems.
<A> A tool such as a hammer for press-fitting a spring washer or a retaining metal fitting is required.
<B> There are also problems of b and c in Example 2 above.
[0006]
In another conventional wear warning device (see Japanese Utility Model Publication No. 8-1306), a cylindrical holding member is inserted and fixed in a through hole provided in a back plate of a brake pad, and a probe inserted into the holding member has a circular shape. A pair of stepped portions are formed by changing the position of the columnar head and the non-cylindrical leg portion whose maximum diameter is equal to the head diameter by changing the position by 180 degrees, and provided in the friction material of the pad continuously to the through hole. The probe head is inserted into the blind hole, and in this state, a pair of opposing elastically bendable check claws provided on the inner surface side of the holding member are engaged with the stepped portion to hold the probe. In the mounting structure of the brake pad wear detector, a pair of opposed notches with a tapered head are arranged on the outer periphery of the tip of the probe so as to be disposed in front of the stepped portion. However, it has the following problems.
<A> In order to fix the holding member of the probe (probe assembly with the probe body attached with an electric wire etc.) to the brake pad, the holding member is inserted into the through hole of the back plate in advance, and then the friction material is molded. Manufacture must be integrated into the back plate by processing. Therefore, a core for forming a blind hole is required, the press die becomes complicated, workability is lowered, and it is economically disadvantageous.
<B> Since the direction of the check claw of the holding member must be determined and molded, the operation is further troublesome.
<C> Since the thin holding member protrudes from the back plate of the brake pad, it is not preferable for handling when it is metallic, and there is a risk of damage to other materials even if it is made of other materials. high.
<D> Since the stacked stacking cannot be performed, the management and transportation are troublesome.
<E> The holding member peels off the remaining friction material and reuses it or discards it. In the former case, man-hours are required, and in the latter case, resources are wasted, which is uneconomical.
[0007]
[Problems to be solved by the invention]
An object of the present invention is to provide a wear warning device having a simple structure and capable of easily attaching and detaching a probe.
[0008]
[Means for Solving the Problems]
According to the first aspect of the present invention, the probe main body to which the electric wire is attached has a non-circular head having a wide surface and a narrow surface, and a non-circular cross section provided on the lower side of the neck continuously provided from one of the heads. A spring receiving member comprising a circular body part and a leg part provided continuously from the body part, and having a fitting hole which is fitted to the lower side of the head of the probe body and the head cannot pass therethrough. in, facing the fitting extending to said possible narrow surfaces direction of the non-circular head passage and wide surface direction from Chakuana is impossible pass, further narrow surface of the body portion can pass through the said head And a co- rotating means that is non- rotatably fitted to the non-circular body portion and can be rotated , and biases the spring receiving member toward the head of the probe body. The spring means is contracted between the spring receiving member and the leg of the probe body, and the spring receiving member and the spring hand are attached to the probe body. There are integrated in the back plate to secure the friction member, when said probe body is in a predetermined direction, the narrow face can not insert the upright claws of the non-circular head insertion available-whether Tsubane receiving member If, when the rotation of the probe body in a state in which the non-circular head while bending the spring means is pressed to the back surface of the upright pawls tip the backing plate is protruded from the surface of the back plate, said spring A non-circular hole comprising a wide surface into which the standing claw piece of the receiving member can be inserted is drilled, and when the probe body is elastically attached to the back plate, the wide surface side of the head of the probe body is the back plate side . It is configured such that it is seated and elastically seated on the narrow surface side of the non-circular hole, and the standing claw piece of the spring receiving member is configured to be restricted in rotation by the narrow surface of the non-circular hole of the back plate. This is a friction material wear warning device.
The friction material wear warning device according to claim 1 is the friction material wear warning device according to claim 1, wherein a non-circular shaft portion is formed on a leg portion of the probe main body. is there.
A third aspect of the invention relates to the friction material wear warning device according to any one of the first and second aspects, wherein the diameter of the friction receiving member is increased from the seat portion of the spring receiving member toward the body portion of the probe body. A friction material wear warning device, characterized in that a portion is formed.
Stopper invention according to claim 4, for regulating the wear warning device of the friction material according to either of claims 1 to 3, the amount of movement of the spring receiving member in the direction away from the head of the probe body A friction material wear warning device, characterized by comprising means.
According to a fifth aspect of the present invention, there is provided the friction material wear warning device according to the fourth aspect, wherein the compression coil spring wound around the body portion of the probe body is in close contact, and the movement amount of the spring receiving member is regulated. The friction material wear warning device is characterized in that it is a stopper means.
According to a sixth aspect of the present invention, in the friction material wear warning device according to the fourth aspect of the present invention, the spring receiving member is disposed on the anti-spring receiving member side of the compression coil spring wound around the body of the probe body. A friction material wear warning device characterized in that a winding portion having a coil diameter with which a hanging claw piece can abut is formed as a stopper means for restricting a moving amount of a spring receiving member.
According to a seventh aspect of the present invention, there is provided the friction material wear warning device according to the fourth aspect, wherein the spring member is attached to the leg portion of the probe main body and holds the anti-spring receiving member side of the spring means. The friction material wear warning device is characterized by forming a flange portion with which a diameter-enlarged portion of the receiving member can come into contact to form a stopper means for restricting the amount of movement of the spring receiving member.
[0009]
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1
Hereinafter, embodiments of the present invention will be described with reference to FIGS.
[0010]
<B> Outline of friction material wear warning device The friction material wear warning device detects wear of a friction material used for a drum brake or a disc brake, and is attached to a back plate to which the friction material is fixed. A probe main body to be attached, a spring, a spring receiving member, and the like are provided.
[0011]
<B> Probe body The probe body 1 is for electrically detecting the wear limit position of the friction material. For example, as shown in FIG. A neck lower shaft portion 15 provided continuously, a non-circular trunk portion 16 having a square cross section continuously provided to the neck lower shaft portion 15, and a leg portion 18 provided continuously from the trunk portion 16 are provided.
Non-circular head 10 described above, for example, or a shape like a track athletic field formed of circularly arcuate surfaces which form a parallel surface forming a narrow face 14, the wide surface 13, also oval But it ’s okay.
The probe main body 1 uses an insulating material, for example, a thermosetting component material in which various fillers such as glass fiber and inorganic filler are blended based on silicon resin.
Further, the probe main body 1 is formed with a protrusion 11 on the top of the non-circular head 10 and an electric wire hole 12 through which the electric wire 4 for wear detection is passed. Further, a groove 17 in which a retainer or the like can be fitted is formed between the body portion 16 and the leg portion 18. Further, a parallel surface 19 is formed on the leg portion 18 so as to be easily grasped with a finger.
[0012]
<C> Brake Pad Taking a disc brake as an example, the brake pad 3 is integrally formed with the friction material 31 on the back plate 30 by molding or the like, as shown in FIGS. A non-circular hole 32 is formed in the back plate 30. The non-circular hole 32 is similar to the non-circular head 10 of the probe body 1 and is formed to be slightly larger so that the head 10 can pass through.
[0013]
<D> Spring receiving member The spring receiving member 2 holds one side of the compression type coil spring 5 that is externally mounted on the body portion 16 of the probe main body 1, and has a function of attaching and detaching the probe main body 1 to the back plate 30 and rotation. For example, as shown in FIGS. 3 and 4, the member includes a fitting hole 20, a standing claw piece 21, a hanging claw piece 22 , a seat portion 23, and a diameter-expanded portion 24.
Fitting Chakuana 20 formed in the seat 23, non-rotatable relative to the body portion 16 of the probe body 1, and a hole in the axial direction can move, a standing pawl 21 press molding of the hanging claw 22 For the sake of simplicity, it has a substantially square shape with notches 25 at the four corners.
The standing claw piece 21 facing the narrow surface 14 of the head 10 has a function of fitting into the wide part of the non-circular hole 32 of the back plate 30 to restrict relative rotation, and is one piece or opposite. Two pieces to stand upright from the inner surface of the fitting hole 20. Further, the standing claw piece 21 also has a function of contacting the back surface side of the periphery of the narrow surface of the non-circular hole 32 and compressing the spring 5, and two pieces are desirable from this functional surface.
Hanging claw 22 is formed as needed, is intended to smooth the move in the axial direction to expand the sliding surfaces of the body portion 16 of the probe body 1, Chakuana 20 2 pieces of the opposing fitting It hangs down from the inner surface orthogonal to the upright claw piece 21.
Enlarged diameter portion 24 is formed as needed, ing and retaining part of the finger when you remove the probe body 1 and the spring receiving probe assembly 6 with integrated like member 2. Accordingly, the enlarged diameter portion 24 may have a trumpet shape as in this example, or may be formed as an opposing strip-shaped piece to reduce the weight.
[0014]
<E> probe assembly probe assembly 6, lines 4 to the probe body 1, the spring receiving member 2 is obtained by integrating a coil spring 5, as shown in FIG. 5, the probe body 1 of the leg portion 18 After inserting the spring receiving member 2, the coil spring 5, and the cup washer 51 in this order from the side , the coil spring 5 is compressed and the retainer 50 is fitted into the groove 17 to integrate them. Instead of the coil spring 5 of this example, a disc spring or a corrugated leaf spring can be used.
The electric wire 4 detects the wear limit position of the friction material 31, and both ends of the electric wire 4 are inserted into the electric wire hole 12 from the direction of the head 10 of the probe main body 1 and arranged so as to be folded back on the protrusion 11. In this way, the tip forms a U-shaped loop, and the inner periphery thereof is in contact with the protrusion 11 and is regulated in position, so that it can be visually confirmed and the reliability of detecting the use limit of the friction material 31 is high.
The example of FIG. 5 is a exposed type retrofitting the wire 4 to the probe body 1, it can also be applied to a buried type molded integrally therein.
The contraction tube 40 is contracted and fixed in a state in which the loop of the electric wire 4 is in contact with the protrusion 11, and depends on the material of the contraction tube 40, for example, by applying a temperature of about 120 ° C. A portion extending from the leg portion 18 of the electric wire 4 is covered and protected by a covering member 41.
[0015]
<F> Work procedure for attaching the probe assembly to the back plate The work procedure for attaching the probe assembly 6 to the back plate 30 is performed as shown in FIG. First, to insert the parallel surface 19, 19 parts of the probe body 1 of the leg portion 18 as shown in FIG. 6 (A) by grasping with the fingers, the head 10 of non-circular in the non-circular hole 32 of the back plate 30. At this time, the tip of the standing claw piece 21 of the spring receiving member 2 comes into contact with the back surface of the back plate 30.
Subsequently, as shown in FIG. 6B, when the coil spring 5 is pressed until it comes into close contact, the head 10 protrudes from the back plate 30 and the spring receiving member 2 is fitted into the body 16 of the probe body 1. The landing hole 20 (see FIG. 4) and the hanging claw piece 22 are engaged, and relative rotation becomes impossible. In this operation, the position of the probe main body 1 is accurately determined by simply pressing until the coil spring 5 comes into close contact, so that the positioning operation is easy.
At this time, when the coil spring 5 is in close contact, it functions as a stopper means.
Thereafter, the probe assembly 6 from this state, a predetermined angle, for example, as in FIG. 6 (C), rotated 90 °, upright pawls 21 to reach the wide surface of the non-circular hole 32.
The standing claw piece 21 is instantaneously fitted into the non-circular hole 32 as shown in FIG. 6D by the elastic force of the coil spring 5, and the rotation of the probe assembly 6 is restricted. At this time, since the seat portion 23 of the spring receiving member 2 collides with the back plate 30 and emits a hitting sound, a clear signal for completion of assembly is obtained. At the same time, the peripheral portion of the wide surface 13 of the non-circular head 10 (flange surface) is seated on the narrow surface of the peripheral portion of the non-circular hole 32 (surface of the back plate). If the sliding direction of the braked member, which is a rotating member, is set to the arrow X direction, the wire 4 can be reliably cut.
The probe assembly 6 can be removed by placing a finger on the enlarged diameter portion 24 and pulling the coil spring 5 until it comes into close contact with the probe assembly 6 and rotating it 90 degrees.
[0016]
Second Embodiment of the Invention
Hereinafter, other embodiments will be described. The same parts as those of the first embodiment described above are denoted by the same reference numerals, and description thereof will be omitted.
An example in which the probe assembly 6 of FIG. 5 is applied to a brake shoe 7 of a drum brake is shown in FIG. The probe assembly 6 is attached to a shoe rim which is a back plate 30 of the brake shoe 7. As is well known, the friction material 31 is integrated on the front surface of the back plate 30 and the web 70 is integrated on the back surface so as to form a T-shaped cross section .
[0017]
Embodiment 3 of the Invention
The probe assembly 6 of FIG. 8 is another example in which the cup washer 51 and the retainer 50 of the probe assembly 6 of FIG. Several turns on one side of the coil spring 5 are used as a close-contact winding 52 having an inner diameter that matches the body portion 16 of the probe body 1, and the end winding portion of the close-contact winding 52 is further reduced in diameter. It is configured by being fitted into a groove 17 formed between the leg portions 18.
When the probe assembly 6 of FIG. 8 is attached to the back plate 30, the tip of the hanging claw piece 22 of the spring receiving member 2 abuts against the closely wound portion 52 of the coil spring 5 and its movement is restricted, and functions as a stopper means. The
[0018]
Embodiment 4 of the Invention
The probe assembly 6 shown in FIG. 9 has a flange 53 formed on the cup washer 51 of the probe assembly 6 shown in FIG.
When mounting the probe assembly 6 of FIG. 9 in the back plate 30, the distal end of the enlarged diameter portion 24 of the spring receiving member 2 is in contact with the movement to the flange portion 53 of the cup washer 51 is restricted, that acts as a stopper means .
[0019]
【The invention's effect】
Since the present invention is as described above, the following effects can be obtained.
<A> The probe assembly can be easily attached to and detached from the back plate without using a tool.
<B> When the probe assembly is assembled to the back plate, stopper means for restricting the amount of movement of the spring receiving member in the probe axial direction is provided, so that even an unskilled person can easily and accurately perform the operation. .
<C> When the standing claw piece of the spring receiving member is inserted into the non-circular hole of the back plate, the spring receiving member collides with the back plate and emits a hitting sound. be able to.
<D> Since the probe assembly can disassemble and assemble its constituent parts into a single body, in the unlikely event that a defective part occurs, the part can be replaced and is economical.
[Brief description of the drawings]
1 is a perspective view of a probe body according to the present invention. FIG. 2 is a front view of a probe assembly attached to a back plate of a brake pad. FIG. 3 is a cross-sectional view taken along line III-III in FIG. FIG. 5 is a left half sectional view of the probe assembly. FIG. 6 is an explanatory view of the work procedure for attaching the probe assembly to the back plate. FIG. 7 is a diagram showing the probe assembly on the back plate of the brake shoe. Sectional view of the attached main part [FIG. 8] Left half sectional view showing another probe assembly [FIG. 9] Furthermore, left half sectional view showing another probe assembly [Explanation of symbols]
1... Probe body 10 .. head 11 .. projection 12 .. wire hole 13 .. wide surface 14 .. narrow surface 15 .. lower neck portion 16 .. trunk portion 17. · Leg 19 · · Parallel surface 2 · · · Spring receiving member 20 · · Fitting hole 21 · · Standing claw piece 22 · · Dropping claw piece 23 · · Seat portion 24 · · Diameter expansion portion 25 · · Cutout portion 3 ... Brake pad 30 ... Back plate 31 ... Friction material 32 ... Non-circular hole 4 ... Electric wire 40 ... Shrink tube 41 ... Coating member 5 ... Spring 50 ... Retainer 51 ... Cup washer 52 .. Close winding part 53 .. Flange part 6... Probe assembly 7... Brake shoe 70.

Claims (7)

A probe main body to which an electric wire is attached includes a non-circular head having a wide surface and a narrow surface, a non-circular body having a non-circular cross section provided on the lower side of the neck provided continuously from one of the heads, It consists of legs that run continuously from the section,
A spring receiving member having a head fitting which not pass through Chakuana while being fitted to the neck lower side of the head of the probe body, and extending from said fitting Chakuana the narrow width of the non-circular head Standing claw pieces that face the narrow surface of the head so that the surface direction can pass and the wide surface direction cannot pass, and further the body part can pass, and the non-circular body part are non- rotatably fitted. and Mawari possible co-rotation means brought Te is formed,
Spring means for urging the spring receiving member toward the head of the probe main body is contracted between the spring receiving member and the leg of the probe main body, and the spring receiving member and the spring means are attached to the probe main body. Is integrated,
The back plate to secure the friction member, when the probe body is in a predetermined direction, and the non-circular head insertion available-whether Tsubane receiving upright pawls impossible insertable narrow face member, the upright pawls when rotating the probe body in a state of projecting the non-circular head while by pressing flexed spring means on the rear surface of the front end piece the back plate from the surface of the back plate, standing pawl of the spring receiving member A non-circular hole consisting of a wide surface into which the piece can be inserted is drilled,
When the probe body is elastically attached to the back plate, the wide surface side of the head of the probe body is seated and elastically seated on the narrow surface side of the non-circular hole of the back plate, and the spring receiving member is raised. A friction material wear warning device characterized in that the claw piece is configured to be restricted in rotation by a narrow surface of a non-circular hole in a back plate.   2. The friction material wear warning device according to claim 1, wherein a non-circular shaft portion is formed on a leg portion of the probe main body.   The friction material wear warning device according to any one of claims 1 and 2, wherein a diameter-expanding portion that expands from a seat portion of the spring receiving member toward a body portion of the probe body is formed. A friction material wear warning device. In the wear warning device of the friction material according to either of claims 1 to 3, and further comprising a stopper means for restricting the amount of movement of the spring receiving member in the direction away from the head of the probe body A friction material wear warning device.   5. The friction material wear warning device according to claim 4, wherein a compression coil spring wound around the body of the probe main body is in close contact with each other, and is a stopper means for restricting the amount of movement of the spring receiving member. Friction material wear warning device.   5. The friction material wear warning device according to claim 4, wherein a hanging claw piece of the spring receiving member can be brought into contact with an anti-spring receiving member side of a compression coil spring wound around the body portion of the probe main body. A friction material wear warning device, characterized in that it forms a winding portion of a coil diameter and is a stopper means for restricting the amount of movement of the spring receiving member.   5. The friction material wear warning device according to claim 4, wherein a diameter-enlarged portion of the spring receiving member is applied to a holding member that is attached to a leg portion of the probe main body and holds the anti-spring receiving member side of the spring means. A friction material wear warning device characterized in that it forms a contactable flange portion and is a stopper means for restricting the amount of movement of the spring receiving member.

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